That's that katy perry "roar" song. It is finally time, today, to find out which high school wins our huge katy perry event. The superstar challenged high schools nationwide to make your video to her megahit, "roar." Out of the -- I can't even count how many submissions we got. Katy narrowed it down to five incredible messages that touched all of our hearts. All five schools came out in force last week to show their spirit. As we announced they were the finalists. Katy is about to reveal which school she'll be at friday. The winning school to perform a special concert. First, let's look at how we got here. &#9834; Step into the fire &#9834; Reporter: She's the megastar, queen of the jungle. &#9834; And you're gonna hear me roar &#9834; Reporter: When katy perry released her most recent hit song, she hoped it would inspire her legion of fans. Well, america, get ready to "roar." Reporter: So, she teamed up with "gma" to challenge high school students across the country to let out their own special roar with a jungle-sized prize. I'm just going to show uppal your school on the day of my birthday. Reporter: The response was amazing. And the heartfelt submissions poured in. Starting a viral headlines around the country. Katy perry challenged students, make a rendition of her video. They roar across the country. Reporter: As katy scoured through the submissions, she was blown away by the creativity and power of the individual messages. I'm so encouraged because there's so much school spirit in these videos. Reporter: As difficult as it was, katy narrowed it down to five schools and chose the finalists. Each with their own remarkable story. From a young girl with downs syndrome, fulfilling her dream of becoming a cheerleader. To the brave students at cooper high, who held up their deepest fears and shared them with the world. Each one special, capturing katy's message of what it means to roar. Katy's toughest position is on its way. For one of the amazing schools, their roar is about to be the loudest yet. I'm coming to your football field or your classroom, whatever you have. I'm coming there. &#9834; You're going to hear me roar &#9834; all right. Here we go. Katy, is with us live, in london. She is shooting a music video for her brand-new song, "unconditionally." She is with us again to tell us. Katy, go ahead. Tell us who have you chosen? Okay. This decision has been one of the hardest decisions ever that I've ever had to make because there was over 1,000 submissions. But the high school that I have determined the winner, is lakewood high. Oh. Lakewood high. Look at that. You're looking at lakewood high. Just absolutely roaring. Yeah. Amazing. I wish you could see them. They are already wild. They have to be the best concert crowd ever. We cannot wait to be with you in colorado. Do we have a camera set up in colorado? We can ask them how it feels? All right. Katy, let me ask you. What in the world -- honestly. What was it that stood out about this group? They were fantastic. Well, you know, it was really difficult because every story submitted was very unique. Some were heartbreaking. Some were very emotional and vulnerable. And some were exciting and funny. But for me, lakewood really embodied a whole school spirit. I think that they brought everyone together. And you saw so many different people coming together, to do one shot. It was all shot in one shot. All the way to the very end. And it was so incredibly crafted and all different types of, like, school -- you know, the clubs and the cliques. They all came together and did their own individual thing. But it was so interesting and well done and well organized. And I give a big round of applause to whoever organized it because that was thousands of kids coming together to roar. And that's what this competition embodies for me. Katy, thank you so much. And thank you so much for spending the time. You really inspired students all over the country to come together, as you just said. And you know a good video when you see one because you make the best. We want to go to lakewood right now. Courtney is representing lakewood high. And, courtney, you've got katy listening, live in london, where she's making her own video. Can you tell her what this means to you to be chosen? It just means so much. I am just so happy. And I want to thank "gma" and katy perry and everyone who was involved. I don't even know what to say, I'm so excited. You know, your smile says it all. The spirit of that school. Katy, anything you want to say to courtney? You did a great job. You're a great student body president, whatever you're doing, keep on doing it because you're really showing that school spirit still exists. And it hasn't died. You made it come alive with a roar. One last thing. One last thing, right? Katy, the schools worked so hard. And we all know how tough they were. You have something you want to say to the other schools, as well, right? Yes, I do. I just wanted to share a special little gift that I wanted to give all of the finalists. I have made a plaque for each and every one of them, the other four schools get. And I want to say thank you so much. I had so much fun watching those videos. And they mean everything to me. This has been such a great process. All right. Wow. There it is. Katy perry "prism." And one little reminder, it's katy's birthday next friday. And she'll be spending it at lakewood high. And I know, katy, you have one more announcement? Yes. I have something very special for my friend, megan, from verada high school. I want to bring megan to a special event with me as my date, at an event, I'm singing. I know which one it is. It's going to be very exciting. We're going to get dressed up. And I want to celebrate her and hear her roar in person. Megan, thank you so much. I love you. I love your spirit. You have really inspired me. Katy, there's no doubt about it. We all made friends from watching the videos that you inspired those kids to make. We love them all. Thank you so much, katy, for taking the time to do this. Let's take one more loving look

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